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<head><meta charset="utf-8"><title>I-prioritize #76387 Optimisation-caused UB during cross-cra… · t-compiler/wg-prioritization/alerts · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/index.html">t-compiler/wg-prioritization/alerts</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html">I-prioritize #76387 Optimisation-caused UB during cross-cra…</a></h3>

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<a name="209198080"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209198080" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> triagebot <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209198080">(Sep 05 2020 at 22:16)</a>:</h4>
<p><span class="user-group-mention" data-user-group-id="3111">@WG-prioritization/alerts</span> issue <a href="https://github.com/rust-lang/rust/issues/76387">#76387</a> has been requested for prioritization.</p>
<h1><a href="https://forge.rust-lang.org/compiler/prioritization/procedure.html#assign-priority-to-unprioritized-issues-with-i-prioritize-label">Procedure</a></h1>
<ul>
<li>Priority?</li>
<li>Regression?</li>
<li>Notify people/groups?</li>
<li>Needs <code>I-nominated</code>?</li>
</ul>



<a name="209198980"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209198980" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209198980">(Sep 05 2020 at 22:47)</a>:</h4>
<p>I'd say P-high? Looks pretty bad but they haven't said it's a regression</p>



<a name="209199475"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209199475" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209199475">(Sep 05 2020 at 23:05)</a>:</h4>
<p>yup, confirmed not a regression</p>



<a name="209216074"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209216074" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Léo Lanteri Thauvin <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209216074">(Sep 06 2020 at 08:50)</a>:</h4>
<p>Let’s ping LLVM group for this?</p>



<a name="209221721"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209221721" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209221721">(Sep 06 2020 at 11:45)</a>:</h4>
<p>I'm not sure it's LLVM</p>



<a name="209221726"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209221726" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209221726">(Sep 06 2020 at 11:45)</a>:</h4>
<p>It sounded like a MIR opt gone bad</p>



<a name="209221776"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209221776" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209221776">(Sep 06 2020 at 11:46)</a>:</h4>
<p>Oh wait they said</p>
<blockquote>
<p>Dead Argument Elimination</p>
</blockquote>
<p>So yeah, LLVM</p>



<a name="209221781"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209221781" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209221781">(Sep 06 2020 at 11:46)</a>:</h4>
<p>Would be nice to have a reproduction in C then</p>



<a name="209222417"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209222417" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Léo Lanteri Thauvin <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209222417">(Sep 06 2020 at 12:03)</a>:</h4>
<p>+1 for <code>P-high</code></p>



<a name="209222625"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209222625" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> triagebot <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209222625">(Sep 06 2020 at 12:08)</a>:</h4>
<p>Issue <a href="https://github.com/rust-lang/rust/issues/76387">#76387</a>'s prioritization request has been removed.</p>



<a name="209552154"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552154" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552154">(Sep 09 2020 at 18:51)</a>:</h4>
<p><span class="user-mention" data-user-id="255061">@LeSeulArtichaut</span> <span class="user-mention" data-user-id="232545">@Joshua Nelson</span> I've just seen that you have agreed on <code>P-high</code> but it seems <code>P-critical</code> to me</p>



<a name="209552365"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552365" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552365">(Sep 09 2020 at 18:53)</a>:</h4>
<p>sounds fine to me, <span class="user-mention" data-user-id="123586">@nagisa</span> also suggested P-critical</p>



<a name="209552379"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552379" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552379">(Sep 09 2020 at 18:53)</a>:</h4>
<p>I understand that this is an LLVM issue and maybe that make us lower a bit the priority, on the other hand I think I'd rather tag this kind of issues as <code>P-critical</code> as in the end they affect Rust very badly and there's something we can do, like backing out the LLVM  11 upgrade if needed</p>



<a name="209552606"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552606" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552606">(Sep 09 2020 at 18:55)</a>:</h4>
<p>anyway, I wanted to discuss this <span aria-label="point up" class="emoji emoji-1f446" role="img" title="point up">:point_up:</span> briefly to see what others do and think, my opinion is that I wouldn't lower the priority of an issue because it's LLVM or a Rust 3rd party dependency because they still affect Rust and almost always there's something we can do :)</p>



<a name="209552736"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552736" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552736">(Sep 09 2020 at 18:56)</a>:</h4>
<p>my reasoning originally is that no one had come across it for 5 years, but if it's unsound it should probably higher yeah</p>



<a name="209552757"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552757" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552757">(Sep 09 2020 at 18:56)</a>:</h4>
<p>ok :)</p>



<a name="209552770"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552770" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552770">(Sep 09 2020 at 18:56)</a>:</h4>
<p>but in general, what do you think about my thoughts?</p>



<a name="209552781"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209552781" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209552781">(Sep 09 2020 at 18:56)</a>:</h4>
<p>regardless of this particular issue</p>



<a name="209553651"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209553651" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Joshua Nelson <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209553651">(Sep 09 2020 at 19:02)</a>:</h4>
<p>makes sense :)</p>



<a name="209553895"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209553895" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209553895">(Sep 09 2020 at 19:05)</a>:</h4>
<p>anyway, back to this particular case, I'm kind of having second thoughts about the priority of it :)</p>



<a name="209553930"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209553930" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209553930">(Sep 09 2020 at 19:05)</a>:</h4>
<p>was checking and yeah this issue exists since a TON</p>



<a name="209553983"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209553983" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209553983">(Sep 09 2020 at 19:05)</a>:</h4>
<p>in general I tend to think that soundness issues are always <code>P-critical</code> but ... unsure ...</p>



<a name="209554039"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209554039" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209554039">(Sep 09 2020 at 19:06)</a>:</h4>
<p>cc <span class="user-mention" data-user-id="116083">@pnkfelix</span> who might want to also weigh in</p>



<a name="209554675"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209554675" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> apiraino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209554675">(Sep 09 2020 at 19:11)</a>:</h4>
<p>Can we assign the best label based on our estimate, then tomorrow during the meeting it will be discussed anyway and possibly the priorty adjusted?</p>



<a name="209561309"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209561309" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209561309">(Sep 09 2020 at 20:10)</a>:</h4>
<p>yes, that would be ok</p>



<a name="209561348"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209561348" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209561348">(Sep 09 2020 at 20:10)</a>:</h4>
<p>but just in case, I've already labelled as <code>P-critical</code></p>



<a name="209561362"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/209561362" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#209561362">(Sep 09 2020 at 20:11)</a>:</h4>
<p>just mentioned Felix in case they wanted to give an opinion</p>



<a name="210061704"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/210061704" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> apiraino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#210061704">(Sep 14 2020 at 20:52)</a>:</h4>
<p><span class="user-mention" data-user-id="116266">@Santiago Pastorino</span>  According to last week's meetings notes, the issue is being actively worked on, can we remove the I-prio label?<br>
<a href="#narrow/stream/238009-t-compiler.2Fmeetings/topic/.5Bweekly.20meeting.5D.202020-09-10.20.2354818/near/209658278">https://rust-lang.zulipchat.com/#narrow/stream/238009-t-compiler.2Fmeetings/topic/.5Bweekly.20meeting.5D.202020-09-10.20.2354818/near/209658278</a></p>



<a name="210062645"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/210062645" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#210062645">(Sep 14 2020 at 21:00)</a>:</h4>
<p>there's no <code>I-prioritize</code> label in this issue</p>



<a name="210062663"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/210062663" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#210062663">(Sep 14 2020 at 21:00)</a>:</h4>
<p>unsure what did you mean exactly</p>



<a name="210063381"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/210063381" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> apiraino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#210063381">(Sep 14 2020 at 21:07)</a>:</h4>
<p>ignore me</p>



<a name="214202344"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/214202344" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Léo Lanteri Thauvin <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#214202344">(Oct 22 2020 at 15:19)</a>:</h4>
<p><span class="user-mention" data-user-id="125294">@Aaron Hill</span> <span class="user-mention" data-user-id="116083">@pnkfelix</span> (if you want to discuss here for LLVM cherry-pick)</p>



<a name="214252977"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/214252977" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#214252977">(Oct 22 2020 at 21:55)</a>:</h4>
<p>to backport I guess the commit should be cherry-picked to <a href="https://github.com/rust-lang/llvm-project">https://github.com/rust-lang/llvm-project</a> and then on the rust repo just update the llvm-project submodule</p>



<a name="214252984"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/214252984" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#214252984">(Oct 22 2020 at 21:55)</a>:</h4>
<p>example <a href="https://github.com/rust-lang/llvm-project/pull/81">https://github.com/rust-lang/llvm-project/pull/81</a></p>



<a name="214252997"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/214252997" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#214252997">(Oct 22 2020 at 21:55)</a>:</h4>
<p>cc <span class="user-mention" data-user-id="125294">@Aaron Hill</span></p>



<a name="214253403"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/214253403" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Aaron Hill <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#214253403">(Oct 22 2020 at 22:00)</a>:</h4>
<p>I'm writing a regression test, and I'll open a rustc pr bumping llvm soon</p>



<a name="214254866"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize%20%2376387%20Optimisation-caused%20UB%20during%20cross-cra%E2%80%A6/near/214254866" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Aaron Hill <a href="https://rust-lang.github.io/zulip_archive/stream/245100-t-compiler/wg-prioritization/alerts/topic/I-prioritize.20.2376387.20Optimisation-caused.20UB.20during.20cross-cra.E2.80.A6.html#214254866">(Oct 22 2020 at 22:17)</a>:</h4>
<p>Opened <a href="https://github.com/rust-lang/rust/pull/78253">https://github.com/rust-lang/rust/pull/78253</a></p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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